From skim@unam.mx Tue Jan 16 14:39:47 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!unam!skim From: skim@unam.mx (Seo-yeon Kim) Newsgroups: comp.dsp Subject: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jan16.143947.9764@unam.mx> Date: Tue, 16 Jan 1996 14:39:47 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: WinVN 0.99.5 Lines: 11 A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. At 14.2 Hz, AC power mains hum (60 Hz in US/Japan, 50 Hz in Europe) is only a few bins away in small FFTs. A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width. What sampling rates are people using for their vinyl rips? 44.1 kHz or 48 kHz DAT? -- Seo-yeon Kim "Marcus is not one man." 486DX4/100 (FreeBSD 2.0.5) / AmigaOS 3.1 From slaurent@netcom.com Tue Jan 16 22:18:47 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!netcom!slaurent From: slaurent@netcom.com (Sun-mi Laurent) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jan16.221847.8885@netcom.com> Date: Tue, 16 Jan 1996 22:18:47 GMT References: <1996Jan16.143947.9764@unam.mx> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1996Jan16.143947.9764@unam.mx>, skim@unam.mx (Seo-yeon Kim) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Sun-mi Laurent -- NETCOM On-Line Communication Services "Tape doesn't lie at 02:14. Ears do." From mmartinez@stanford.edu Wed Jan 17 05:07:47 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!stanford!mmartinez From: mmartinez@stanford.edu (Mikhail Martínez) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jan17.050747.2378@stanford.edu> Date: Wed, 17 Jan 1996 05:07:47 GMT References: <1996Jan16.143947.9764@unam.mx> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: Netscape 1.1N Lines: 12 In article <1996Jan16.143947.9764@unam.mx>, skim@unam.mx (Seo-yeon Kim) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. > At 14.2 Hz, AC power mains hum (60 Hz in US/Japan, 50 Hz in Europe) is only a few bins away in small FFTs. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Mikhail Martínez Opinions expressed are solely my own and not those of Stanford University Computer Systems Lab. ------------------------------------------------------------ From sokonkwo@berkeley.edu Wed Jan 17 17:27:47 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!berkeley!sokonkwo From: sokonkwo@berkeley.edu (Seo-yeon Okonkwo) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Jan17.172747.3174@berkeley.edu> Date: Wed, 17 Jan 1996 17:27:47 GMT References: <1996Jan16.143947.9764@unam.mx> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Jan16.143947.9764@unam.mx>, skim@unam.mx (Seo-yeon Kim) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. Don't forget that if you downsample to 64 Hz first, your FFT resolution jumps to 0.015 Hz per bin with a modest 4096-point transform. -- Seo-yeon Okonkwo *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0